The Industrial Raspberry Pi Forum

Hi

Please would it be possible for you to clarify some points about your Connect and gate modules:
- For a first proof-of-concept we intend to use your PROFINET RevPi gate to interface with a Siemens 1511C-PN PLC. Can you confirm that this will be suitable?
- Can you give me an idea of the performance of the Connect unit when dealing with PROFINET traffic?
- Can we use a larger memory card if required or is the supplied card ‘locked’ in?
- We intend to use a Revolution Pi Connect unit. Does the Connect come with a PiBridge Plug or will we need to order that separately?

- Yes, the Siemens 1511C-PN PLC has a PROFINET IRT interface so the RevPi Gate PROFINET IRT Slave will be able to exchange data with it.
- The performance depends on the update cycle of the PiBridge. The more modules you need the longer the cycles will be. So if you have just a RevPi Connect Module with only one RevPi Gate PROFINET IRT you will have about 5 ms cycle time on the PiBridge. So worst case scenario you need two cycles to receive a change of the data and another two cycles to react which will be about 20 ms.
- The memory on the Compute Modules´ eMMC chip is fixed to 4Gb. But you may use i.e. an USB stick to extend the data. There are also industrial grade USB sticks for DIN rail mounting available. Anyway with regard to the lifetime of the eMMC, it's better to minimize write access or to use alternative storage devices such as cloud storage.
- Yes, you have to order the PiBridge plug separate for the RevPi Gate Modules. This is necessary because the RevPi Gates have been available before the RevPi project existed, see here.

Thanks very much for your reply, Dirk.